The present invention claims priority under 35 U.S.C. xc2xa7119 of German Patent Application No. 101 40 801.3 filed Aug. 20, 2001, the disclosure of which is expressly incorporated by reference herein in its entirety.
1. Field of the Invention
The invention relates to an apparatus for treating a fibrous web, e.g., a paper and/or board web, in which the fibrous web, either alone or together with at least one supporting belt, e.g., a dewatering belt, press belt, or mesh belt, is guided over at least one moving or stationary supporting surface. On the side of the fibrous web facing away from the supporting surface, at least one sealing device is provided, which includes a sealing element which is held in a holder.
2. Discussion of Background Information
An apparatus, such as the one generally discussed above, is described, e.g., in German Patent Application No. DE-A-197 16 131.6.
The relevant sealing device is often provided in the area of an air-based device such as in particular a stabilizer box or the like. In this case, an additional vacuum zone can be provided in the upper area of such a stabilizer box. Between the two vacuum zones, that is to say between the upper and the lower vacuum zone a seal can be provided, in particular a seal fixedly mounted on the box.
The present invention provides an apparatus of the type mentioned at the beginning in which the sealing element can be replaced without difficulty, i.e., replacement may be possible even without dismantling the stabilizer box. If appropriate, the intention is for such a change even to be possible behind the framing part.
According to the invention, the present invention provides an apparatus for treating a fibrous web such as in particular a paper and/or board web, in which the fibrous web, on its own or together with at least one supporting belt, e.g., a dewatering belt, press belt, mesh belt and/or the like, is guided over at least one moving or stationary supporting surface. On the side of the fibrous web facing away from such a supporting surface, at least one sealing device is provided, which includes a sealing element which is held in a holder which is arranged in the immediate vicinity of the supporting belt without touching the latter, i.e., while maintaining a gap between the sealing element and the supporting belt. It is possible for the sealing element to be guided out of the holder laterally, i.e., transversely with respect to the web running direction.
Therefore, the sealing element forming a wearing part can be drawn laterally out of the holder without difficulty, without adjacent devices in the papermaking machine, such as in particular an adjacent stabilizer box or the like, also having to be dismantled for this purpose. It may possibly be necessary, before drawing out the sealing element, for a lateral seal, a lateral cover or a lateral air knife to be removed, but this is possible with minimum effort.
The holder is expediently provided with a corresponding guide, along which the sealing element can be drawn laterally out of the holder.
As already mentioned, the sealing device can be provided, for example, in the area of an air-based device used in particular in a press section or a drying section, such as in particular a steam blower box, a suction box, a stabilizer, ventilation fittings and/or the like.
The sealing element can be formed, for example, by a flexible sealing blade.
According to a preferred embodiment of the apparatus according to the invention, the sealing blade, held at the edges in the holder, can be acted on by a pressing element in such a way that it becomes curved out of the maintenance and/or changing position towards the supporting belt and, as a result, assumes its operating position, in which a sealing section is in the immediate vicinity of the supporting belt.
The unloaded sealing blade held at the edges in the holder is advantageously at least substantially flat, with which it assumes its maintenance or changing position.
The distance between the sealing section of the sealing element and the supporting belt can expediently be set via the pressing element.
The pressing element is preferably formed by a pressing blade, which expediently has a greater stiffness than the sealing blade.
The pressing element can, for example, be accommodated in a recess in a carrier preferably formed by an air-based device. In this case, the recess can be covered at least partly by the pressing blade.
The pressing element can advantageously also be guided out of the holder laterally, that is to say transversely with respect to the web running direction. The holder can again also be provided with a corresponding guide for this purpose.
For the purpose of changing, after the load on the sealing element has been relieved, both the sealing element and the pressing element can be drawn laterally out of the holder provided with corresponding guides, and therefore drawn laterally out of the papermaking machine.
In principle, however, the sealing element can also be formed by a sealing strip. This sealing strip can be mounted fixedly or in a compliant or sprung manner.
According to an expedient practical embodiment of the apparatus according to the invention, the sealing strip is held in a holder which is supported in a sprung manner on the bottom of a recess in a carrier preferably formed by an air-based device.
In specific cases, it is also advantageous if the sealing strip is held in a holder which is pivotably mounted in the area of a recess in a carrier preferably formed by an air-based device.
The holder can be adjustable, for example pivotable, via at least one actuating element. In this case, for example, the use of hydraulic, pneumatic and/or electromechanical actuating elements is conceivable.
The holder can, for example, also be capable of being folded back, so that the sealing element can be removed from the holder after the latter has been folded back.
According to a further advantageous embodiment, in an air-based device, the sealing device separates two zones which can be acted on with different pressures.
In specific cases, it is also advantageous if the sealing device is provided in combination with an air-based device used in the drying section, for example a stabilizer box, as a second sealing device, as viewed in the web running direction, in particular over the machine width, in order in particular to separate an upper and a lower vacuum zone from each other.
In this case, the two vacuum zones can for example be connected to separate vacuum sources.
However, an embodiment is also conceivable in which the two vacuum zones are connected to a common vacuum source, and the pressures in the vacuum zones can be set separately, in particular via flaps or the like. The first sealing device on the inlet side, as viewed in the web running direction, can be formed, for example, by a flexible, floating seal, a mechanical sealing strip or an air knife.
As already mentioned, the sealing device can in particular also be provided for other vacuum boxes, for example in the press section.
During operation, the sealing element is expediently secured against slipping laterally by a locking means, for example cotter pins (and so on).
The holder having the guide for the sealing element can be connected rigidly or in a compliant or sprung manner to the air-based device.
In specific cases, it is also advantageous if the sealing element is provided with a camber, that is to say as viewed over the machine width, has a different distance from the supporting belt, for example a wire. As a result, for example wire deflection between edge and center can be compensated for.
The sealing element can in particular include plastic, for example GRP, Teflon, CRP or the like, or else of another plastic, or of metal.
The two vacuum zones can be sealed off laterally for example via air knives and/or mechanical sealing plates which, in order to release the sealing element, are removable or adjustable, in particular displaceable.
The sealing element can extend over the entire machine width or else only over part of the machine width or can be divided over its width into at least two zones.
The present invention is directed to an apparatus for treating a fibrous web that includes at least one supporting surface arranged to support a surface of the fibrous web, and at least one sealing device positionable adjacent a surface of the web opposite the surface of the web supported by the at least one supporting surface. The at least one sealing device includes a sealing element and a holder structured and arranged to hold and to enable lateral sliding movement of the at least one sealing device cross-wise to a web travel direction.
According to a feature of the invention, the lateral sliding movement can facilitate installation and removal of the at least one sealing device.
In accordance with another feature of the invention, the fibrous web may include at least one of a paper and board web.
Further, at least one supporting belt may be arranged to support and guide the fibrous web over the at least one support surface and past the at least one sealing device. The at least one supporting belt can include at least one of a dewatering belt, press belt, and mesh belt. Still further, the sealing device may be positioned adjacent a surface of the at least one supporting belt opposite the surface supporting the fibrous web. The at least one supporting surface may be structured and arranged to be one of a moving or stationary surface.
According to still another feature of the instant invention, the sealing element may be structured and arranged to form a non-contacting seal with the fibrous web.
In accordance with a still further feature of the present invention, the holder may include a guide structured and arranged to laterally draw the sealing element out of the holder.
An air-based device can be provided, and the sealing device can be coupled to the air-based device. The air-based device may include at least one of a steam blower box, a suction box, a stabilizer, and ventilation fittings. Further, the air based device can be positionable in one of a press section and a drying section.
Moreover, the sealing element can include a flexible sealing blade. Further, a pressing element can be structured and arranged so that, when the sealing blade held in the holder, the pressing element is positionable to move the sealing blade from one of a maintenance or changing position to an operating position, and the pressing element is positionable to move the sealing blade from the operating position to the one of a maintenance or changing position. The sealing blade may include a sealing section, which, when the sealing blade is in the operating position, can be located in vicinity of the surface of the fibrous web opposite the surface supported by the at least one supporting surface. The sealing blade in the one of a maintenance or changing position can be at least substantially flat, and the sealing blade in the operating position can be curved. Still further, a distance of the sealing section of the sealing blade from the fibrous web can be set via the pressing element. A supporting belt can be arranged to guide the fibrous web over the at least one supporting surface and past the at least one sealing device, such that a distance of the sealing section of the sealing blade from the supporting belt can be set via the pressing element. The pressing element may include a pressing blade, and the pressing blade can have a greater stiffness than the sealing blade. The pressing element may be accommodated in a recess in a carrier, and the carrier can include an air-based device. The recess is at least partially covered by the pressing blade, and the pressing element may be structured and arranged to be laterally guidable out of the holder.
In accordance with another feature of the invention, the sealing element can include a sealing strip, The sealing strip can be mounted fixedly. Further, the sealing strip may be mounted in a compliant or sprung manner. The sealing strip can be held in the holder, which is coupled to a recess of a carrier via a spring. Moreover, the spring can be coupled to a bottom of the recess and the carrier comprises an air-based device. The sealing strip may be held in the holder, which is pivotably mounted in an area of a recess in a carrier comprising an air-based device.
An actuating element can be structured and arranged to pivotably adjust the holder.
According to still another feature of the invention, the holder may include a guide element that is pivotable relative to the sealing element to facilitate removal of the sealing element.
Further still, an air-based device can be provided, and the sealing device may be structured and arranged to separate two zones which are acted on with different vacuum pressures.
The apparatus can be provided in combination with an air-based device positioned within a drying section, such that the combination includes the sealing device positioned as an intermediate seal to separate an upper and a lower vacuum zone from each other. Further, the air-based device can include a stabilizer box. The two vacuum zones may be couplable to separate vacuum sources, or the two vacuum zones may be couplable to a common vacuum source. The two vacuum zones may also be separately settable via flaps. A second seal, located upstream, relative to the web travel direction, from the intermediate seal can be one of a flexible, floating seal, a mechanical sealing strip and an air knife. A locking device can be structured and arranged to secure the sealing element from laterally slipping out of the holder. The locking device may include one of a cotter pin and a clamp. The holder can have a guide structured to receive the sealing element that is one of rigidly connected or in a compliant or sprung manner to the air-based device. The sealing element may include a camber. Further, the sealing element can include at least one of plastic or metal, and the plastic may include at least one of GRP, Teflon, CRP. The two vacuum zones may be laterally sealable via at least one of air knives and mechanical sealing plates which, in order to release the sealing element, are at least one of removable and adjustable.
According to still another feature of the invention, the sealing element may extend over an entire machine width.
In accordance with still yet another feature of the present invention, the sealing element may extend over only a part of a machine width or is subdivided over its width into at least two zones.
The present invention is directed to an apparatus for treating a fibrous web that includes at least one supporting surface arranged to support a surface of the fibrous web, at least one supporting belt arranged to guide and support the fibrous web over the at least one supporting surface, and at least one sealing device positionable adjacent a surface of the at least one supporting belt opposite the surface supporting the fibrous web. The at least one sealing device includes a sealing element and a holder structured and arranged to hold and to enable lateral sliding movement of the at least one sealing device cross-wise to a web travel direction.
Other exemplary embodiments and advantages of the present invention may be ascertained by reviewing the present disclosure and the accompanying drawings.